Balancing machine



Jvan. 29, 1924. 1,481,785

' N. W. AKIMOFF l BALANCNG MACHINE Filed April 26, 191.8

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C/m Vf/@Hwy Y Patented dan. 29, w24..

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NICHOLAS W. AKIMOFF,

OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T VIBRA- TION SPECIALTY COMPANY, 0F PHILADELPHIA, PENNSYLVANIA, A CORPORATION 0F DELAWARE.

'BALANCING MACHINE.

vApplication inea April 2e, 191s. serial no. 231,017'.

To all 'whom t 'may concern.

Be it known that I, NICHOLAS W. ARIM- orr, a citizen or subject of the constituted government of Russia, who has declared his 5 intention of becoming a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State offPennsyl- Vania, have invented certain new and useful l Improvements in Balancing Machines, of 1.0 whichthe following is a specification.

ft My invention relates to balancing machines, and it has particular relation to a machine for determining, for the purpose of correction, the location and valuev of static and dynamic imbalance existing in rotatable machine elements.

The principal object of my presentinvention-1s to provide a novel and improved type of machine for testineV rotatable machine elements to determine tie location and value of static and dynamic imbalance existing therein. For the accomplishment of the foregoing object my invention contemplates the provision of a machine in which the ma.- chine elements to be tested may bemounted and rotated in suitable supporting devices of such construction 'and arrangement whereby the machine element being tested may be lpermitted to alternatively oscillate in what may be termed two degrees of freedom,7 either of which may be suppressed at will, so that the machine element maybe tested in a single machine for the ascertainment of the location and value of both static and dynamicfunbalance, and which when permitted lto oscillate simultaneously in both degrees offreedom will show whether or not i .all the proper corrections have -been made for the elimination of such imbalance, both static and dynamic.

My invention further contemplates the provision of means whereby the moments of l inertia of the oscillatory supporting devices may be arbitrarily varied for the purpose of better synchronizing the periods of oscilla- V tion of the oscillatory supporting devices rwith the' speed of rotation of machine element to be tested to thereby accentuate the static or dynamic unbalance existing therein and thus facilitate the determination of the location and value thereof.-

My invention further contemplates the provision of means for stabilizing or' cen' trally locating the oscillatory supporting devices which means incidentally act to modify the respective lperiods of supportino devices, ,and -Which means are also ,provi ed with means for varying their respective tensions whereby chronizing of the respective periods of oscillation of said supporting .devices will not be interferedwith. Y

The nature and characteristic features of my invention will be more readily understood from the following description taken in connection with the accompanying drawings forming parthereof, in which:

Figure l isa front elevation of a balancing machine embodying the main features of my-present invention.

Fig. 2 is an end elevation thereof:

Fig. 3 isan end elevation of a portion-of the supporting structure;

Fig. 4f is an elevational view of a clamp or device for creating a determinable counterbalancing centrifugal force for the purpose of overcoming the existing Istatic and dynamicunbalance in the machine element to be tested. c

Referring to the drawings, in theparticular embodiment of my invention .therein oscillation of said f the proper synshown, 5 is the stationery base of a machine upon which a framework G 1s mounted in such manner as to be capable of periodic os` cillation transversely to the axis Aof the machine element to bel tested. The means of mounting the frame 6 with respect tothe stationary vbase 5 may comprise hinges 7 in terposed between' the bottom of the frame 6 'and the base 5. Other means of mounting the frame G in such manner asto permit the desired periodic oscillation o-f the same'will readily occur to those skilled in the art.

The frame 6 is provided at the top with a table 8 upon which the devices for supporting the machine element to be tested may be secured. f

The frame 6 is provided, for a purpose to be presently more fully explained, with means for varying the moment of inertia about thel axis of oscillation of said frame .and the. parts carried thereby. 'The means l for varying the moment of inertia as shown rawings comprises the provlslon, at

in the '4o 1 top of the table 8. On each side of the axis each end of the frame 6, of a vertical rod9, upon which. a weight 10 is adjustably mounted, .there being means provided such as the set screws 11 for securing the weight `10 at any desired location' on the vertical rod 9; y Y

On each side of the axis of oscilla-tion there is provided a spring 12 which serves to stabilize or maintain the location of the frame 6 in a normal central osition, -and these springs 12 also incidental y modify the period of oscillation of said frame 6 about the axis thereof, The tension of the springs 12 may be altered at the will of the operatorby means of adjusting screws 13, and

there is thus provided one means for arbiy `the determination of the location and value of static and dynamic imbalance existing therein. The other end of the shaft 18 ofthe machine element is supported on rollers 2O whicli-are journalled in aframe 21 whichis mounted on the top of the table 8 in such manner as to permit oscillatory movement vof the end of the shaft 18 which is supported by the rollers 20. In the present instance this object is accomplished by pivotally connecting the frame 21 as at 22 -with a base member'i23 Which'is suitably secured on the of oscillation of the frame 21 there is pro- -vided a spring 24 which serves to stabilize or centrally locate the frame 21 and incidentally modifies the period of oscillation thereof, vand the springs 24 are also provided with means for varying their tension which means of oscillation.

may Acomprise the adjusting screws 25, so

-thatthe period of oscillation of the means for'supporting the end of the shaft-18 may in this manner be arbitrarily varied under the control of the operator. The oscillatoryv frame 21 is also provided with means for varying the moment of inertia about its axis The means for varying the moment of inertia in the present instance 'comprises'rods extending from each side of 'the frame 21 upon which rods 26 are` mounted shiftable weights 27 which may be secured in anyT desired position by means of the set screws 28. z The oscillatory frame 21 'is also provided with set screws 29 which i serve as .a means for locking the frame 21 against oscillatory movement when desired.

Mountedon the rameh is an electric motor 30 which serves as a means for rotating the machine element 19 through belting 31 oi' other power transmission mechanism.

The speed of the niotor 30 is under the control ot' the operator by means .of a rheostat 32 wherebytbc speed of rotation of the Inachine element being tested may be varied to synchronize the same with the period of oscillation of the particular portion of the supporting mechanism which. is permitted to oscillate. accordingly as the operator Ldesires to test for static ordynaniic imbalance,

as will be hereinafter more fully set forth. y

Any desired mea-ns ofsetting up a deterininable centrifugal force may be mountedv on the shaft 18, and a device for this purpose is shown in Fig. 4, which device there shown constitutes the subject mattei' of an application for Letters Patent previously filed by me on May 11, 1917, Serial No. 167,919. This device comprisesan elliptical frame or yoke 35 which is symmetrical about each of its two axes at' right angles to the axis of rotation. At each end of the frame 35 there is preferably provided a boss or lug 3G 'interiorly threaded for the mounting of oppositely disposed set screws 37. The set screws 37 are of the same shape and size and are each provided at their inner ends with saddle blocks 38 for engaging the surface of the shaft 18 upon which the applicance is mounted. All the parts of this device are accurately made, calibrated and balanced, so that when the appliance is centrally adj usted upon the shaft. there will be no centrifugal effect when the shaft is rotated. By adjusting the set screws 37 the centre of gravity of the traine 35 may be thereby displaced to any desired distance from the center of the shaft 18 to thereby create a centrifugal force which will be in functional relationship to thc mass of the frame 35, to the radius of displacement. and also to the i'ate of the angular speed. It will be readily understood thatany other preferred form ofapparatus may be employed. if desired for creat' ing a. determinab-le centrifugal force for the purpose of temporarily counterbalancing the static or dynamic imbalance existing in the machine element under test.

For the purpose of indicating when the required standard of balance has been reached through the counterbalancing'effect. of theI device above describedthere may be provided in connection with the machine any preferred form of device which will indicate the condition arrived at. there may be employed the common type of dial gauges which are well known and in common use. lThese devices as shown may be arranged'as followsg-The base 5 of the machine may be provided with an integral extension 40 in which is rigidly mounted an upwardly extendingbar 41 which supports a dial gauge 42 at its upperend in proximity icoA For 'this purpose anced has its shaft provided with a flange- 17 l which is lsuitably supported in the groovedrollers 16 which are journalled in the bracket which is rigidly attached tov 'the top of the table 8; and the other end of the shaft 18 of the machine element 19 is supported on the rollers 20 Which are journailed in the oscillatory frame 21. The set screws 29 are now screwed down so that they each bear against the base member 23 which is secured .to the top of the table 8, thus locking the oscillatory frame 21 against movement 4about its axis 22. The set screws 14 located at the` bottom of the oscillatory frame.. 6` are retracted -so as to permit the frame 6 to oscillate about its axis as provided by the hinges 7. The counterbalancing-device shown in detail in Fig. 4 having previously been placed upon the end of the shaft 18, the motor 30 is then caused t0 opi- 'erate and through .the 4belt 31 the machine element 19 vvill be rotated. By successivel trial in various positions both radially and as to oifcenter displacement the counterbalancing device Will finally be brought lto a condition Where the same Will"counteract any static unbalance existing in the machine element- 19. .The speed of rotation,is varied by means of therheostat 32'to approximate the speed of-rotation of said machine element tofthatzofthe period of free' oscillation of the frame -6 and the parts carried thereby. The' shiftable Weights' 10 provide. a

means forvarying the period of free oscil- .lation of the fra-me 6 and the parts carried therebybychangingthe moment of inertia of said table about the axis of oscillation. `The springs12 vfhich serve to.y normally maintain the frame 6 in a central location may be varied in their vtension by means of the screws y13 so as to adjustl and synchronize the same to the-.desired period of free oscillation and thus facilitate the ready oby servation ofthe `desired standard of unbalance, 'the same'being indicated by the dial sauge@ j After the angular location and extent of thestatic unbalance existing in the machine element under testv has been indicated by observing the angular location of the counterbalancing :device vand also measuring. the amount of oftcenter adjustment thereof, the -static unbalance can then be readily elimi- "element lunder test.

nated by the removal of the required qualitity of material on the heavy side ofthe machine element or by the addition of a similar mass on the lightside5 Whichever' may be most convenient or permissible.

When the machine element has thus been brought to a condition of substantially perfect static balance, the machine element is again replaced in the machine and the set screws 14 are ,thenscreived' down against the base 5 to thus lock the frame 6 against oscillation and the set screws 29 carried by the oscillatory frame 21 are thenA retracted so as to permit the end of the shaft supported by the rollers 20 to oscillate laterally.'

ance existing therein is then ascertained through successive trial and by angular and offcenter adjustment of the` counterbalaneing device. The moment of-inertia of the oscillatory frame 21 and the parts carried thereby may be varied by shifting the Weights 27 on their-.supporting rods 26, and

thevsprings 24 which normally serve to locate theoscillatory frame 21in a central-position may be variediin their tension bymeans of the adjusting screws 25 so asto i ,synchronize the period of free oscillation of the frame 21 and the parts carried thereby with the speed of rotation of the machine lVhen the. counterbalancing device is finally brought to a condition Where the existing dynamicunbalanee vis substantially counteracted, the angular andlongitudinal position of the same is observed, as well as the amount of oifcenter displacement thereof, so that the operator may then determine the amount of material to be removed or added at proper and permissible places to elim-inate said dynamic unbalance.

It Will thus be noted that there is provided a machine in which the location and value of both static and dynamic` unbalance existing in rotatable machine elements may be readily determined, and that said machine is characterized by the provision of suitable supporting 'devices which are so constructed and arranged that the machine element under test may be permitted to alternatively oscillate intwo degrees of fredom, the Will of the operator, and which is provided With means for completely synchronizing the periodof free oscillation of the supporting devices andthe parts carried thereby with the speed of rotation of the machineelement being tested so that the accuracy of the determination will be insured.

Having thus desf'zribed the nature and either of whichl may be suppressed at.

sti

characteristic features of my invention, lwhat II claim` as new and desire to secure by Lettiers Patent is;

1. In a machine for determining the location and value of static and dynamic iinbalance existing in a rotatable machine element, means for rotatably supporting saidl machine elementwhereby the same may be permitted to oscillate in two degrees Vof freedom, means for alternatively suppressing the-oscillation in either degree at will,

- and means for arbitrarily creating a deterininable centrifugal force for counterba-lmancing the static or dynamic unbalance ,dom, means for alternatively suppressing the oscillation in either degree', and means adapted to be shiftably mounted on a portion of said machine element for arbitrarily creating a determinable centrifugal force for counterbalancing the static-or dynamic imbalance existing in' said machine element.

3. In a machine for determining the location and value: ot static and dynamic iinbalance existing in a rotatable machine element, means for rotatably supporting said vmachine element whereby the saine vmay be permitted to oscillate in two degrees ot' free- "dom, .means y tor alternatively suppressing' the oscillation in either degree at will, means for arbitrarily creating adeterminable centrifugal force for coiinterbalancing the staticor dynamic imbalance existing-in said machine element, and means for rotating the lmachine ele-ment at variable speeds. .Y

4; In a machine for letermining the location and value of static and dynamic iinbalance existing in a' rotatable machine element,` means for rotatably supporting said machine element whereby the same may be 'permitted to oscillate in two' degrees ot fre- .dom, means for alternatively suppressing;l

the oscillation in either degree at will, means t'or arbitrarily creating a determinable centrifugal force for counterbalancing the static or dynamic imbalance existing in said machine element, means for rotating the machine element at variable speeds, and means for synchronizing the period ot oscillation in each degree of freedom with the speed of rotation of said machine element.

5. In a machine tor determiningthe'location and value of static and dynamic unbalance existing in a rotatable machine element,.means for rotatably supporting said machine element whereby the same may be permitted. to oscillate in two degrees of freedom, means for alternatively suppressing the oscillation in either degree at will, means maires adapted to be shiftably mounted on a portion ot said machine element for arbitrarily creating a determinable centrifugal force for counterbalancing the static or dynamic unbalance existing in said machine element,

and means for rotating the machine element at variable speeds. 6. In a machine tion and value of static and dynamic unbalance existing in a rotatable machine element, means for rotatably supporting Said machine element whereby the same ma be permitted to oseillate in two degrees of reedom, meansl for synchronizing'the period oi' oscillation` in each degree of freedom with the speed of rotation of said machine element.

7. A balancing machine for determining the location and value of static and dynamic unbalance existing in a rotatable machine.4

element comprising a stationary base, an oscillatory fra-me mounted thereon, devices mounted upon said frame for rotatably supl porting each end of said machine element, one of said devices being rigidly connected to said frame and the other of said supporting devices being capable ot oscillation with respect thereto, means for arbitrarily locking the frame against oscillation, means for arbitrarily locking the oscillatory supporting device carried thereby against oscillation, and means adapted to be mounted on the rotatable machine element for arbitrarily creating a determinable centrifugalv force for counterbalancing the static or dynamic unbalance existing in said machine element.

8.' A balancing machine for determining the location and value of static and dynamic unbalancee-xisting in a rotatable machine element comprising a stationary base, an oscillatory fra-me mounted thereon, devices mounted upon said f1 ame for rotatably supporting each end ot said machine element, one of said' devices being rigidly connected to said trame and the other ott said supporting` devices being capable ot oscillation with respect thereto, means for arbitrarily locking the frame against oscillation, means for arbitrarily locking the oscillatory supporting device carried thereby against oscillation, means adapted to be mounted on the rotatable machine element for arbitrarily creating a determinablecentrifugal force for counterbalancng the static or dynamic unbalance existing in said machinel element, and means for rotating the machine element at variableV speeds.

9. A balancing machine for determining for determining the locathe location and value of static and dynamic unbalance existing in arotatable machine ing the frame against oscillation, means for arbitrarily locking the oscillatory supporting device carried thereby against oscillation,

' means adapted to be mounted on the rotatable machine element for arbitrarily creating a deterininable centrifugal force for counterl balancing the static or' dynamic imbalance existing in said machine element, means for rotating the machine element at variable speeds, means for synchronizing the period of oscillation of the.I frame with the speed of rotation of Athe machine element, and means for synchronizingthe period of oscillation of the oscillatory supportingdevice carried by said frame with the-speed of rotat-ion of the machine. element. i

10. A balancing machine forrdetermining y lthe location and value'ot static and dynamic ried thereby,

' chine element` for arbitrarily creating a deimbalance-existing in a rotatable machine element comprising a stationary base. an oscillatory frame mounted thereon. devices' mounted upoirsaid frame for rotatably supporting each end ot' said machine element. one of said devices being rigidly connected to said frame and the-other of. said supporting deyices being capa-ble f oscillation. with respect thereto, mans for arbitrarily locking the frame against oscillation, means for arbitrarily locking the 'oscillatory supporting device carried thereby against oscillation, means for arbitrarily varying the moment of inertia. of said -frame and the parts carmeans for arbitrarily varying the moment of inertia of the supporting de vices carried byV said traine, and means adapted to be mounted on the rotatable materminable centrifugal force for counterbalancing the static or dynamic 'imbalanceV existing in said machine element. l

1l. A balancing machine for determining the location and value of static and dynamic unbalance existing in a rotatable machine element comprising a stationary'y base, an os- `cillatory frame mountedfthereon, devices mounted upon lsaid trame for rotatably supporting each end of said machine element,

one of said devices being rigidly connected to said `frame andthe other ofsai'd supporting devices being capable'of oscillation with respect thereto, means for arbitrarily locking the frame against oscillation, means Vfor ardevice carried y means for arbitrarily varying the moment of vinertia of said frame and thelocation and the 'parts carried thereby, means for arbitrarily varying the moment of inertia of the supporting devices carried by said frame, vmeans adapted to bev mounted on the rotatable machine element for arbitrarily creating a determinable centrifugal force for counterbalancingthe static or dynamic imbalance existing in said ma-- chine element, and means for rotating the machine element zit-Variable speeds.

12.A balancing machine for4 determining the location and value of staticand'dynamic unbalance existing in,a rotatable "machine element comprising a. stationary'base, an oscillatory frame mounted thereon, devices mounted upon said franiefor rotatably supporti-ngeacli end ofsaid machine element,

vone of said devices being rigidly connected to said frame and the otherof said supporting devices being capable of oscillation with respect thereto, means for arbitrarily locking the framel against oscillation, means for -arbitrarily locking the oscillatory supporting device carried lthereby against oscillation, means fora-rbitrarily varying the moment-of 'inertia' of said` frame and the parts carried thereby, means for arbitrarily varying the moment of inertia of the supporting devicesearried by said frame, means for arbitrarily creating a determinable centrifugal force for counterbalanciin-g the static on dynamic unbalance existing in said machine element` and means for :rotating the machine element at variable speeds.

13. A balancing machine for determining the location and value of statici-and dynamic imbalance existing in a rotatable machine element comprising a stationary base, an oscillatory frame mounted mounted upon said frame for rotatably supporting each end of said machine element, one of said devices being rigidly connected to said frame and the other` of said supporting devices being capable of oscillation with respect thereto` means for arbitrarily locking the frame against oscillation, means for thereon,` devices ios arbitrarily locking the oscillatory support Vdevices carried by said frame, andmeans for arbitrarily creating a determinable centrifugal force for counterbalancing the static ordynamic-unbalance existingin said machine elementj- 14. A balancing .machine for determining value of static and dynamic imbalance' existing in a rota table -machine element comprising a stationary base, an oscillatory frame mounted thereon, devices device carried thereby against oscillamounted upon ysaid frame for rotatably supporting each end of said machine element, l'

'one of said devices being rigidly' connected of the oscillatory supporting device carried by said frame with the speed of rotation of the machine element, springs for stabilizing the oscillatory frame in a normal central position, means for varying the tension of said springs, springs for stabilizing the oscillatory supporting device carried by the frame in a normal central position, and means for varying the tension of said springs.

"19'. A balancing machine for determining the location and value of static and dynamic imbalance existing in a rotatable machine element comprising a stationary base, an

oscillatory frame mounted thereon. devices mounted upon said frame for rotatably supporting each end of said machine element, one of said devices being rigidly connected to said frame and the other of said supportvtion, means for arbitrarily varying the moment of inertia of said frame and the parts carried thereby, means for arbitrarily varying the moment of inertia of the oscillatory supporting device carried by saidframe, means for arbitrarily creating a determinable centrifugal force for counterbalancing the static or dynamic imbalance existing in said machine element, means for rotating the machine element at variable speeds, springs for stabilizing the oscillatory frame in a normal central position, means' for varying the tension of said Asprings, springs for stabilizing the oscillatony supporting device carried by the frame iii-fa, normal central position, and means for varying the tension of said springs.

Q0. A balancing machine for determining the location and value of static and dynamic unbalance existing in a rotatable machine element comprising a stationary base, an oscl'll `,ory frame mounted thereon,' devices mounted upon said frame for rotatably supporting each end of said machine element, one of said devices being rigidly connected 59 to said frame and the'other of said supporting devices being capable of oscillation with ing devices being capable of oscillation with respect thereto. means for arbitrarily locking the frame against oscillation, means for arbitrarily locking the oscillatory supporting device carried thereby against oscillation, means for arbitrarily varying' the m0- nient of inertia of said frame and the parts carried thereby, means for arbitrarily varying the moment of inertia of the oscillatory supporting device carried by said frame.

means adapted to be mounted on the rotatable machine element for arbitrarily creating a deteiminable centrifugal force for counterbalancing the static or dynamic unbalance existing in said machine element. means for rotating the machine element at variable speeds, springs for stabilizing the oscillatory frame in a normal central position. means for varying the tension of said springs, springs for stabilizing the oscillatory supporting devices carried by the frame in a normal central position, and means for varying the tension of said springs.

2l. A balancing machine, comprising an (.scillatory member, a pivotmounting for said member operative to restrain said member to cscillate in a single plane, a support for a body to be tested carried by said member. a pivot. connection between said support and said member operative to restrain said support to oscllate in a single plane with respect to said member and at an angle With said first plane. so that said support possesses tivodegrees 'of freedom. and'means to prevent the loscillation of either of said member, or said support with respect to said member. selectively or simultaneously.

22. A balancing machine, comprising a base, almember pivotally carried by said base and limited to one degree of freedom, a support for a body to be tested pivotally carried by said member and limited to one degree of freedom ivith respect to said member, means to rotate a body carried by said support, thus giving said support two degrees of freedom, and means to restrain the movement of said support to either one of said degrees of freedom.

In testimony whereof I have hereunto signed my name.

NICHOLASy W. AKIMOFF. 

